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Entry  Tue Oct 26 10:41:46 2021, Mehrpad Monajem, External trigger and drs_exam 
    Reply  Tue Oct 26 12:00:51 2021, Stefan Ritt, External trigger and drs_exam 
       Reply  Tue Oct 26 15:05:18 2021, Mehrpad Monajem, External trigger and drs_exam 
Message ID: 846     Entry time: Tue Oct 26 15:05:18 2021     In reply to: 844
Author: Mehrpad Monajem 
Subject: External trigger and drs_exam 

Thanks for your reply.

1- I want to have a window size of 25.6ns instead of 200ns at 5GSPS. I have a 200khz high voltage pulser, which applies a pulse to my sample. I want to digitize the detector signal for each pulse (each pulse has a 25.6ns period). The pulser and digitizer use same 200khz trigger signal from each channel of the signal generator.

2- My DRS board has a 2048 combined stick on it. But the software distribution that I have doesn't contain the drs_exam_2048.cpp program. Could you please send the link that I can download this program? I can't find it under the link below.

link: https://www.dropbox.com/sh/clqo7ekr0ysbrip/AACoWJzrQAbf3WiBJHG89bGGa?dl=0

Best regards,


Stefan Ritt wrote:

1. Why should your waveform start from 0 to 5ns? I don't get your point. Whenever you trigger a readout, you get a 200ns wide time window, and by definition it starts at zero.

2. In the software distribution you have a drs_exam_2048.cpp program. Note that your board needs to be physically modified before delivery to switch to 2048 bins.


Mehrpad Monajem wrote:

Hi Stefan,

I have two problems regarding using the drs_exam file with external trigger:

1- I connected a 200Khz signal with 20ns rising edge, 50 ohm load, and 27% duty cycle as an external trigger. The output of the drs_exam file starts from 0 to 200ns. Since I use an external trigger, I think it should be starting from 0 to 5ns and then again starting from 0. Could you please tell me where the problem is?

2- How is it possible to change from 1024 to 2048 bins in the drs_exam example?


You can find my code in the attachment.

Best regards,



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